I have the same error as amo001. When installing Win7, everything seems OK until boot, where you get the error message "User profile not loaded". I can also confirm that the method proposed by amo001 works.

1) Delete the Users folder on the new external disk containing Win7
2) Use robocopy to copy a fresh install of the C:\Users folder to the external disk.

I used Virtualbox for this, and mounted the VHD image of a fresh Win7 install as a disk to achieve this.